采用热重分析（TG）分析沼渣的热解特性,研究沼渣的热解动力学并计算指前因子A、焓变ΔH、吉布斯自由能ΔG、熵变ΔS等热力学参数。进一步考察温度对沼渣热解产物分布与性质的影响。其热解过程可分为3个失重阶段,其中第2阶段为主要失重阶段,采用Flynn-Wall-Ozawa（FWO）法、Friedman法和Kissinger-Akahira-Sunose（KAS）法计算的平均活化能分别为410.00、471.32和420.01 kJ/mol,热力学参数计算结果表明沼渣热解过程具有稳定的能量输出。沼渣热解油的产率随温度上升先增加后降低。气体产物的高位热值（HHV）从400 ℃时的6.82 MJ/Nm3增加到700 ℃时的8.54 MJ/Nm3。红外光谱（FTIR）、拉曼（Raman）光谱表明热解温度升高生物炭结构的有序性增加。
Abstract
Pyrolysis kinetics of biogas residues were researched by FWO, Friedman and KAS methods, and its thermodynamic parameters including pre-exponential factor, enthalpy change, Gibbs free energy and entropy change, were also calculated. In addition, effects of the temperature on pyrolysis products distribution and properties were studied in a fixed-bed reactor with traditional electric heating. The pyrolysis process can be divided into three weightlessness stages, of which the second stage is the main weightlessness stage. The average activation energies calculated by Flynn-Wall-Ozawa （FWO） method, Friedman method and Kissinger-Akahira-Sunose （KAS） method is 410.00 kJ/mol, 471.32 kJ/mol and 420.01 kJ/mol, respectively, Thermodynamic parameter calculation results show that the pyrolysis process of biogas slag has stable energy output. The yield of liquid product increased first and then decreases with the increase of temperature. The high calorific value （HHV） of the gas products increases from 6.82 MJ/Nm3 at 400 ℃ to 8.54 MJ/Nm3 at 700 ℃. FTIR and Raman spectra show that the order of biochar structure increases with raising of pyrolysis temperature.
关键词
热力学 /
热解 /
动力学 /
沼渣 /
热解产物 /
产物分析
Key words
thermodynamics /
pyrolysis /
kinetics /
biogas residue /
pyrolysis product /
product analysis
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基金
国家自然科学基金（52104245）; 重庆自然科学基金（cstc2021jcyj-msxmX0099）; 国家现代农业产业技术体系（CARS-03-40）; 重庆市留创项目（2019LY41）
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